Thank you heclak for your great work !! I have tried 1.4 b11 with SC. Catapult does not work as you had mentioned, yet it DO take off from the SC deck !!
1. Hold W or analog brake when the mission starts to keep the aircraft from skid.
2. Press L-shift + U to tell the deck crew that you are going to launch.
3. Throttle up to the max then let off W or analog brake and there you go !!